Notas sobre Energías Renovables

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Re: Notas sobre Energías Renovables

Mensajepor Fermat » 05 Dic 2017 10:56 am

Este camino despeja la nieve solo con energía solar
Por Enedis (Socio de Artículos), 05/12/2017

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Eurovia ha creado un recubrimiento que despeja nieve de las carreteras con energía solar (Créditos: Eurovia)

Eurovia, una subsidiaria de Vinci, prueba en Doubs y Yvelines un recubrimiento que, capturar la energía solar, se despeja solo de nieve, calentando al mismo tiempo los edificios alrededor.

Esto es lo que se puede llamar una carretera "multifuncional". Llamada Power Road, es desarrollada por Eurovia, una filial de Vinci. Es un camino de energía positiva, que se probará en los departamentos de Doubs e Yvelines (Francia).

Gracias a los tubos completamente reciclables, instalados aproximadamente a un metro por debajo de la carretera, podrá capturar, intercambiar y almacenar energía térmica. Eso hasta un de la energía calorífica 20% solar.

Ahí viene su lado multifuncional: Power Road podrá suministrar calor a los edificios que lo rodean, ya sean locales comerciales, viviendas, oficinas o incluso edificios industriales. Según Eurovia, cada 25m² de vía, aseguran el íntegro de la calefacción de una casa de 70m². El dispositivo también suministrará agua caliente.

En invierno, la energía recuperada se utilizará para calentar el revestimiento y derretir la escarcha o la nieve que lo cubre. El sistema, que también se puede adaptar a las pistas de los aeropuertos, funcionará con una bomba, dispuesta también en el subsuelo. La energía se liberará y pasará por los tubos para subir a la carretera.

Por esto, el constructor espera, que reduzca las operación de vertido de sal y los costos asociados. En verano, a su vez, será cuestión de usar el dispositivo para enfriar los caminos y así, "contribuir a reducir los efectos de las islotes de calor urbanos", dijo Eurovia en un comunicado a mediados de octubre.

Premiado en el Salon des Maires
Durante la presentación del proyecto, afirmó Pierre Anjolras, presidente de Eurovia: "Con Power Road, el camino sigue siendo un camino, pero desempeña un nuevo papel en la transición a una economía libre de carbono porque, por primera vez, al almacenar calor, se posterga la producción y consumo de energía renovable". Aplicable a múltiples usos, Power Road ofrece un potencial de desarrollo importante, a la medida de la densidad de rutas de movilidad en el tejido urbano.

Power Road está en prueba desde julio en el peaje de Saint-Arnoult, Yvelines (aproximadamente 500m² de camino de acceso al estacionamiento de camiones). Contribuye al calentamiento de la planta baja de uno de los edificios de recepción. En agosto, se instaló en el estacionamiento de una escuela secundaria de Pontarlier (Doubs). Extrae su energía de la red de calefacción de la ciudad, que a su vez funciona con un incinerador que aprovecha los desechos domésticos.

La innovación de Power Road fue premiada en la última feria de alcaldes y autoridades locales en París a fines de noviembre. Eurovia ha recibido el trofeo "Infraestructura y crecimiento verde", otorgado por la Federación Nacional de Obras Públicas, en el marco del experimento realizado con la ciudad de Pontarlier.

https://www.latribune.fr/entreprises-finance/la-tribune-de-l-energie-avec-enedis/grace-a-l-energie-solaire-cette-route-se-deneige-toute-seule-760389.html
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Re: Notas sobre Energías Renovables

Mensajepor Fermat » 11 Dic 2017 4:20 am

México generará la electricidad más barata del mundo
El gigante italiano Enel se compromete a producir energía a un precio de 17,7 dólares por MWh en 2020

Ignacio Fariza, México - 8 DIC 2017

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Molinos generadores de energía eléctrica. Getty

La electricidad más barata del mundo se generará, a partir de 2020, en el Estado mexicano de Coahuila (norte del país). El gigante energético Enel se ha hecho, en la última subasta de energía a largo plazo celebrada en México a mediados de noviembre, con un contrato por el que se compromete a generar electricidad a un precio de 17,7 dólares por MWh, el más bajo del mundo según los datos de Bloomberg New Energy Finance, en una planta de 100MW de capacidad instalada que ya está en fase de construcción muy cerca de la frontera con Estados Unidos. Hasta ahora, el precio más bajo se registraba en Arabia Saudí, donde un proyecto de energía solar se compromete a generar electricidad a un precio de 17,9 dólares por MWh.

Al ser un proyecto pequeño respecto a las necesidades eléctricas de México en su conjunto, los especialistas no esperan que tenga una incidencia inmediata en los precios que pagan los consumidores. En cambio, sí abre una importante veta para que el coste de la energía que soportan hogares y empresas baje con fuerza en un futuro no tan lejano.

La electricidad se generará en el parque eólico de Amistad, situado cerca de Ciudad Acuña, según la información proporcionada por la firma italiana. “Una de las razones para que el precio sea tan bajo son las sinergias con las primeras fases del parque: la infraestructura y la interconexión [el factor que muchas veces más encarece los proyectos] ya están construidas”, apunta a EL PAÍS Paolo Romanacci, director general de Enel para México y Centroamérica. En el precio ofertado, el directivo afirma no haber incorporado de antemano los avances tecnológicos que se esperan en los tres próximos años, antes de que el proyecto entre en funcionamiento definitivamente: “Somos una empresa con un bajo perfil de riesgo: la tecnología es la que es, la turbina que utilizaremos ya está desarrollada y tenemos un plan industrial escrito. Estamos seguros y nos salen los números”.

Romanacci tampoco se muestra sorprendido por la cifra ofertada: “Es el más bajo en un contexto global de precios que ya está por ahí”. Tampoco por el hecho de que la electricidad más barata del mundo vaya a provenir de un proyecto eólico y no solar, una constante en los últimos tiempos. “Es un falso mito: es cierto que la solar está mejorando a un gran ritmo, pero la eólica tiene un gran margen de mejora, incluso superior. La industria ha cambiado su estrategia en los últimos años y está siendo más agresiva”, agrega el jefe regional de Enel. Su pronóstico para México, un mercado en el que la energética italiana ha centrado sus miras de futuro, es que ambas tecnologías limpias crezcan en los próximos años por encima de las expectativas: “A estos precios, empieza a no tener sentido ninguna alternativa que no sea renovable”.

Seguir leyendo:
https://elpais.com/economia/2017/12/07/actualidad/1512602315_489392.html
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Re: Notas sobre Energías Renovables

Mensajepor Fermat » 06 Ene 2018 7:52 am

Una opinión, no de oposición a la energía solar, pero si de alerta.

Solar's Bright Future Is Further Away Than It Seems
Tyler Cowen, 2‎. ‎januar‎ ‎2018‎
Yes, panels are cheaper, but much more R&D is needed for a true green energy breakthrough.

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Photographer: Michael Nagle/Bloomberg

There is now a doctrine of what I call “solar triumphalism”: the price of panels has been falling exponentially, the technology makes good practical sense, and only a few further nudges are needed for solar to become a major energy source. Unfortunately, this view seems to be wrong. Solar energy could be a boon to mankind and the environment, but it’s going to need a lot more support and entrepreneurial and policy dynamism.

Varun Sivaram, in his forthcoming “Taming the Sun: Innovations to Harness Solar Energy and Power the Planet” lays out this case in what may be the first important policy book of 2018. To be clear, Sivaram, who holds a doctorate in physics, is a solar expert and an energy adviser -- he’s no enemy of alternative energy sources. He thinks government should increase its support for energy research and development, aiming at diverse pathways, applied at various stages of technology development, and targeting game-changing breakthroughs. In other words, we need to recognize the limitations of today’s solar power if we are going to make it really work.

The first disquieting sign is that solar companies are spending only about 1 percent of their revenue on research and development, well below average for a potentially major industry. You might think that’s because things are going so great, but some major solar users may have already maxed out their technology. According to Sivaram’s estimates, four of the five most significant country users -- Italy, Greece, Germany and Spain -- have already seen solar energy flatten out in the range of 5 percent to 10 percent of total energy use. The fifth country, Japan, is only at 5 percent.

Germany and the state of California have experienced operational problems as solar has grown as an energy source. Because the sun isn’t continuously available, solar power at large scale doesn’t integrate well with the electric grid, which favor steady sources such as fossil fuels or nuclear. Solar power creates an expense for the whole system, even if the panels themselves are cheaper.

Silicon technologies dominate the panel market today, but Sivaram sees greater dynamic potential in perovskite, organic and quantum dot solar cells, and possibly orbital solar power satellites. Breakthroughs in those areas might lower costs and increase solar potency, making the calculus more favorable to green energy.

A common view is that solar power will come into its own once batteries and other storage technologies make steady improvements. Yet Sivaram notes that lithium-ion batteries in particular are not well-designed for storage across days, weeks and months. Also note that about 95 percent of global energy storage capacity is from hydroelectric power, a discouraging sign for the notion that solar energy storage is on a satisfactory track.

Promoting solar energy also isn’t in the interest of regulated utilities. They fear a scenario where many users deploy solar power to detach from the energy grid, either wholly or in part. Other customers’ bills would have to rise to cover the costs of the grid, and that in turn would encourage even more secession into solar and alternate energy sources. Because that scenario is a financial loser for the utilities, regulatory institutions discourage utilities from integrating solar power into the grid, which limits competition.

Solar energy has great potential for emerging economies, but some very basic preconditions are not in place. India, for instance, would need to end its kerosene and electricity subsidies. Freer trade in solar technologies is found in Tanzania and Rwanda but not always in West Africa.

In sum, just improving silicon panel solar technologies may not be enough. Sivaram calls for “systemic innovation,” based on “refashioning entire energy systems -- including physical infrastructure, economic markets, and public policies -- to enable a high penetration of solar energy.” I would add that we should reconsider the abandonment of nuclear energy, a topic that Sivaram touches upon but does not emphasize.

One lesson is that marginal improvements aren’t always enough, and economic dynamism is more important than we have been realizing. A whole series of integrated breakthroughs may be required to move significantly closer to a green energy future. I do think the U.S. will eventually get there, but after reading “Taming the Sun,” I have to wonder if we are up to the challenge now.

https://www.bloomberg.com/view/articles/2018-01-02/solar-s-bright-future-is-further-away-than-it-seems
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Re: Notas sobre Energías Renovables

Mensajepor Fermat » 08 Ene 2018 6:34 am

This Inexpensive Battery Could Revolutionize the Clean Energy Industry
Kyree Leary, 6-Jan-2018

In Brief
A team from Northwestern University has created a lithium-iron-oxide battery that has the potential to power cars and smartphones hours longer than traditional batteries. Best of all, it's inexpensive and rechargeable.


Christopher Wolverton and his team of researchers at Northwestern University, in collaboration with a team of researchers from Argonne National Laboratory, have created a new lithium ion battery that shouldn’t work. For starters, it uses iron, a material that has always failed when used in other batteries. It also uses oxygen in a way scientists used to think would make batteries unusable.

Instead of producing another failing battery, Wolverton and Zhenpeng Yao, a PhD student in Wolverton’s laboratory, used computations to create a new formula that allows it to function. Specifically, they found the right balance of lithium, iron, and oxygen ions that enable the oxygen and iron to cause a chemical reaction that doesn’t result in the oxygen escaping, which would render the battery unstable.

Video: https://www.youtube.com/watch?v=9OVtk6G2TnQ



“The problem previously was that often, if you tried to get oxygen to participate in the reaction, the compound would become unstable,” explained Yao. “Oxygen would be released from the battery, making the reaction irreversible.”

Long-Lasting Impact
In the end, their battery not only works, but it’s rechargeable, cheaper than traditional lithium-cobalt-oxide batteries — as iron is one of the cheapest elements on the planet, and cheaper than cobalt — and has a much higher energy capacity. It could one day be used in smartphones and electric vehicles, thereby boosting their capabilities. According to Wolverton, their new battery could keep phones powered eight times longer “or your car could drive eight times farther.”

Video: https://www.youtube.com/watch?v=Eo0q59NPNUQ



The team’s inexpensive batteries could also help decrease the price of electric vehicles (EVs), putting them on par with gas-powered cars. We’ve seen that people are open to buying EVs, but for some, the price isn’t low enough yet, unless they buy used.

“If battery-powered cars can compete with or exceed gasoline-powered cars in terms of range and cost, that will change the world,” said Wolverton.

Wolverton and his team aren’t finished working on their battery. In fact, Wolverton has since filed a provisional patent with Northwestern’s Innovation and New Ventures Office. He and his team also intend to test other compounds and materials to see if their methods will continue to work. If so, we could see an even wider range of cheaper, more efficient batteries.

https://futurism.com/battery-revolutionize-clean-energy/
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Re: Notas sobre Energías Renovables

Mensajepor Fermat » 12 Ene 2018 6:35 am

Wind & Solar + Storage Prices Smash Records

Imagen
January 11th, 2018 by Christopher Arcus

Tesla solar power plant HawaiiIn a new report from Xcel Energy, the company reported unprecedented low bids for wind and solar with storage. Last year, Xcel announced it would close 660 MW worth of coal-fired power capacity at Comanche Generating Station. Xcel subsidiary Public Service Company issue a request for proposals for wind, solar, natural gas, and storage.

Wind alone was bid at an astonishingly low median price of $18.10/MWh, smashing previous records. A total of 17,380 MW of wind capacity was bid with this as the median price.

The big surprise, however, was the very low bid for wind and solar plus storage. Wind and solar plus battery storage had seven bids for a total of 4,048 MWh at a median bid of $30.60. The energy storage projects ranged from 4 to 10 hours in duration.

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Xcel went on to state, “The response to this Solicitation is unprecedented with over 430 total individual proposals (238 total projects) received from bidders. Over 350 of these individual proposals are renewable energy proposals or renewable energy with storage proposals.” Lithium-ion technology was the only battery storage proposed in this solicitation.

Storage Bid Smashes Previous Record

The previous record for renewable energy plus storage was $.045/kWh, with Tucson Electric Power.

While few details of the projects are known, the bid is lower than any yet revealed. Prior to the Tucson Electric Power bid, two other bids were made public for Hawaii. A bid was set for $0.11/kWh from AES.

Recently, AES joined forces with Siemens to form a new company in the global storage market — Fluence.
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Tesla set a PPA bid at $0.139/kWh in a 20 year contract for solar plus storage, a 13 MW, 52 MWh project completed in March 2017.

Video: https://www.youtube.com/watch?v=fkQBVoS9lAo



It is becoming increasingly clear that wind, solar, and storage are becoming unstoppable, and that coal is on the way out. The newly announced renewables plus storage bids have accelerated that process. With storage breaking records and new solar and wind bids lower than some existing conventional operation and maintenance, the time has arrived.

Imagen

https://cleantechnica.com/2018/01/11/wind-solar-storage-prices-smash-records/
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Re: Notas sobre Energías Renovables

Mensajepor Fermat » 17 Ene 2018 8:01 am

In Colorado, a glimpse of renewable energy’s insanely cheap future
Even with storage, new renewables beat existing coal.

David Roberts@drvoxdavid@vox.com Jan 16, 2018, 2:00pm EST

Imagen
Shutterstock

This month, energy nerds are very excited about a utility bid solicitation.

Wait, hear me out. It really is exciting!

Usually, when we talk about how renewable energy will evolve in the next five years, we rely on analysts and projections. This is different.

When a utility puts out a request for proposals (RFP) — asking developers to bid in for the chance to build new energy resources — the developers who respond aren’t guessing, or boasting. They are laying down a marker that might get called. They are promising only what they are confident they can deliver.

That makes the responses to an RFP a clear snapshot of the state of the industry, relatively unembellished by ideology or public relations spin. This particular snapshot reveals that, on the ground, renewable energy costs are falling faster than even the most optimistic analyst had projected.

(Let’s face it: In most areas of life, when you look past the hype at the real numbers, it’s depressing. Renewable energy is one area where that typical dynamic is diverted. The closer you look, the better the news gets!)

Colorado’s biggest utility seeks lots of new renewables
First, a brief bit of backstory.

The utility in question is Xcel Energy, Colorado’s biggest, which serves 3.3 million electricity customers in the upper Midwest, Colorado, and New Mexico.

In 2016, Xcel released its Colorado Energy Proposal, which was news in itself. The utility proposed to shut down two coal plants in the state and replace their output with roughly 700 MW of solar, 1 GW of wind, and 700 MW of natural gas by 2023. That would put Xcel’s Colorado energy mix at roughly 55 percent renewables. (Xcel’s reasons for ramping up renewable energy are complex — part price, part taking advantage of federal tax credits, part public sentiment.)

Based on that plan, in 2017 the Xcel subsidiary Public Service Company of Colorado issued an “all-source solicitation,” which amounts to the utility saying to private developers: “Here’s how much new power by 2023 we need. Whatcha got?”

At the very tail end of last year, while everyone was busy with the holidays, the company quietly issued a report on the results.

They were mind-blowing. An unprecedented number of developers came forward, eager to build renewable energy and eager to couple it with energy storage, all at unprecedented prices. It seems the people building this stuff are more confident than the analysts writing reports on it.

In Colorado, new renewables are cheap as hell, even with storage

Here’s a high-level overview of the bids and projects received in response to the RFP:
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This is about as striking as spreadsheets get.

First, the scale!

Xcel says that its 2013 all-source solicitation yielded 55 bids. The 2017 equivalent received 430 individual bids, for 238 separate projects. (Sometimes developers bid multiple times on a single project, with different combinations of financing, timeline, etc.)

A total of 350 of the bids involve renewable energy (134 for solar alone), representing more than 100 GW of capacity. Developers are chomping at the bit to build this stuff — partly to claim expiring federal tax credits, partly to claim market share in a booming sector, and partly just because they are human beings and excited about clean energy.

Second, the storage!

The big knock against wind and solar power is that they are variable — they come and go with the weather; they are not “dispatchable.” Critics say their low prices are misleading, because they must be backed up by “firm” capacity that can be turned on and off at will.

One way to make wind and solar more firm (ahem) is to attach storage, which can store excess production during the day when it’s cheap and sell it into the system at night when it’s more valuable. Storage extends the amount of time a renewable energy project is able to operate (its “capacity factor,” in the jargon).

The problem is that adding storage adds considerable cost. But the Xcel bids show that is changing.

The median bid for a wind project was $18.10/MWh; the median for wind+storage was $21, just three dollars higher. The median bid for a solar PV project was $29.50/MWh; the median bid for solar+storage was $36, just seven dollars higher. (Keep in mind what median means: Half the projects bid cheaper than this.)

Here are a few comparisons to help put those numbers in perspective:
•According to Carbon Tracker, based on these bids, new wind+storage energy in Colorado is cheaper than energy from the state’s existing coal plants; solar+storage energy is cheaper than 75 percent of the state’s coal energy. This is worth repeating, because it’s a significant milestone: In Colorado, getting energy from new renewable energy projects with storage is cheaper than getting it from existing coal plants. Coal is dead.
•The cheapest previously known solar+storage price in the US was $45/MWh, in a PPA signed by Tucson Electric last year. The median Xcel bid for solar+storage beats that by $9.
•For the Tucson project, storage added about $15/MWh to the cost of the solar. Compare that to the $3 to $7 added by storage in the Xcel bids. Storage prices are plunging, and as they do, renewables become more competitive.
•The financial advisory firm Lazard issues a much-watched analysis each year of the “levelized cost of energy (LCOE),” a measure that purports to directly compare energy sources based on total costs. Its 2017 analysis estimated that solar+batteries has an LCOE of $82/MWh. You might notice that the median Xcel bid for solar+storage is less than half that. (Important caveats: The Lazard LCOE is for solar with 10 hours of storage, but we do not yet know how much storage is involved in the Xcel bids; Lazard estimates unsubsidized costs, while Xcel projects will benefit from federal tax credits; Lazard’s estimate is for 2017, while developers are effectively bidding 2023 costs. Direct comparisons are difficult. Point is, the number is vaulting down.)

Renewables just keep outpacing expectations

Colorado has excellent solar and wind resources, but it isn’t the only place where real-world bids are racing ahead of official estimates like Lazard’s. Saudi Arabia recently saw bids for utility-scale solar at under $20/MWh, which is less than half Lazard’s lowest estimate for the range of solar LCOE ($46/MWh).

At an auction in Chile last year, a solar+storage project won at $34.40/MWh, which is a third lower than the lowest Lazard LCOE estimates for solar alone.

A company called ViZn Energy Systems, which uses flow batteries rather than lithium-ion, is promising $27/MWh solar+storage by 2023, when the Xcel projects are scheduled to be online. By comparison, Bloomberg New Energy Finance projects an average LCOE of a little higher than that for solar alone in 2030.

What broad averages like LCOE can obscure is that the value of renewable energy (and storage) varies widely from place to place and market to market. In places with competitive procurement of energy (still a minority of energy markets in the world) and good renewable resources, renewables are crushing fossil fuels, even natural gas. Every market like that is a leading wedge, allowing the industry to scale up faster and drive down costs in other markets. This drives a self-reinforcing cycle that analysts looking at averages miss.

That helps explain why reports that focus on real-world projects (“bottom up” reports) tend to be so bullish on renewables. For instance, the latest report on renewable energy costs from the International Renewable Energy Agency (IRENA), drawing on 15,000 data points from projects around the globe, concludes that by 2020, “all the renewable power generation technologies that are now in commercial use are expected to fall within the fossil fuel-fired cost range.” That’s only two years away!

The Xcel RFP in Colorado is a relatively small signal, but it is one of many sending the same message: renewable energy is not “alternative” any more. Costs are dropping so fast it’s difficult to keep track. It is the cheapest power available in more and more places, and by the time children born today enter college, it is likely to be the cheapest everywhere. That’s a different world.

https://www.vox.com/energy-and-environment/2018/1/16/16895594/colorado-renewable-energy-future
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